BACKGROUND: Delayed graft function (DGF) is the main cause of renal function failure after kidney transplantation. This study aims at investigating the value of hypothermic machine perfusion (HMP) parameters combined with perfusate biomarkers on predicting DGF and the time of renal function recovery after deceased donor (DD) kidney transplantation. METHODS: HMP parameters, perfusate biomarkers and baseline characteristics of 113 DD kidney transplantations from January 1, 2019 to August 31, 2019 in the First Affiliated Hospital of Xi'an Jiaotong University were retrospectively analyzed using univariate and multivariate logistic regression analysis. RESULTS: In this study, the DGF incidence was 17.7% (20/113); The multivariate logistic regression results showed that terminal resistance (OR: 1.879, 95% CI 1.145-3.56) and glutathione S-transferase (GST)(OR = 1.62, 95% CI 1.23-2.46) were risk factors for DGF; The Cox model analysis indicated that terminal resistance was an independent hazard factor for renal function recovery time (HR = 0.823, 95% CI 0.735-0.981). The model combining terminal resistance and GST (AUC = 0.888, 95% CI: 0.842-0.933) significantly improved the DGF predictability compared with the use of terminal resistance (AUC = 0.756, 95% CI 0.693-0.818) or GST alone (AUC = 0.729, 95% CI 0.591-0.806). CONCLUSION According to the factors analyzed in this study, the combination of HMP parameters and perfusate biomarkers displays a potent DGF predictive value.
Biomarkers ; Delayed Graft Function ; Graft Survival ; Humans ; Kidney/physiology* ; Kidney Transplantation/adverse effects* ; Organ Preservation ; Perfusion ; Retrospective Studies ; Tissue Donors

OBJECTIVETo investigate the relationship between the survival rate of expanded flap and expansion volume.

METHODSThe minipigs were used and divided into 5 groups according to different expansion volume of the tissue expanders: injection to full content, 50% over content, 100% over content, 0% content and normal control. In each animal, 4 expanders (100 ml) were designed to be implanted at the bilateral side of back. Normal skin control was also designed at the back. The skin histologic change and flap survival rate were detected and analyzed when the expansion volume changed.

RESULTSThe flap survival rate increased along with the increase of expansion volume. While the survival rate decreased when the expansion volume was exceeded to 100% over content.

CONCLUSIONSIn soft tissue and skin expansion, the flap survival rate and the flap size increased as the expansion is over the standard volume, while over-expansion to 100% over content may cause decreased survival rate of expanded flap.

Animals ; Back ; Graft Survival ; Surgical Flaps ; physiology ; Swine ; Swine, Miniature ; Tissue Expansion ; Tissue Expansion Devices

Totipotent and regionally non-specified embryonic stem (ES) cells provide a powerful tool to understand mechanisms controlling stem cell differentiation in different regions of the adult brain. As the development capacity of ES cells in the adult brain is still largely unknown, we grafted small amounts of mouse ES (mES) cells into adult rat brains to explore the survival and differentiation of implanted mES cells in different rat brain regions. We transplanted the green fluorescent protein (GFP)-positive mES cells into the hippocampus, septal area, cortex and caudate nucleus in rat brains. Then the rats were sacrificed 5, 14 and 28 d later. Of all the brain regions, the survival rate of the transplanted cells and their progeny were the highest in the hippocampus and the lowest in the septal area (P<0.01). The grafted ES cells could differentiate into nestin-positive neural stem cells. Nestin-positive/GFP-positive cells were observed in all brain regions with the highest frequency of nestin-positive cells in the hippocampus and the lowest in the medial septal area (P<0.01). mES cells differentiated into end cells such as neurons and glial cells in all transplantation sites in recipient brains. In the hippocampus, the ES cells differentiated into neurons in large amounts. These results demonstrate that only some brain regions permit survival of mES cells and their progeny, and form instructive environments for neuronal differentiation of mES cells. Thus, because of region specific presence of microenvironmental cues and their environmental fields, the characteristics of the recipient tissue were considerably important in formulating cell replacement strategies for neural disorders.
Animals ; Brain ; cytology ; Cell Differentiation ; physiology ; Cell Survival ; Embryonic Stem Cells ; cytology ; transplantation ; Female ; Graft Survival ; Mice ; Rats ; Rats, Sprague-Dawley ; Transplantation, Heterologous ; physiology

BACKGROUNDFor the renal transplant recipients, anemia is one of the common complications and becomes a major medical issue before transplantation. Haemoglobin (Hb) is used as a prognostic indicator, although the optimal pre-transplantation Hb concentration associated with positive prognosis is still controversial. The aim of this study was to detect the optimal Hb concentration on predicting the graft survival and function.

METHODSA retrospective cohort study was conducted by reviewing the medical records of the patients who received renal transplantations at our center from January 2004 to June 2008. Patients were divided into two groups: high Hb group (≥ 100 g/L, n = 79) and low Hb group (< 100 g/L, n = 63). There was no significant difference between the two groups regarding sex, age, blood type and tissue types. Renal function among the two groups was measured and compared. Panel reacting antigens (PRA) of all the recipients were negative. The effect of preoperative hemoglobin concentration on the postoperative renal function recovery in both groups was further analyzed.

RESULTSA total of 14 acute rejection episodes occurred, including 5 patients in the high Hb group (7.9%) and 9 in the low Hb group (11.4%, P > 0.05). The serum creatinine level at one-year post-transplantation of the low Hb group was significantly higher than that of the high Hb group ((117.8 ± 36.3) µmol/L vs. (103.1 ± 35.5) µmol/L, P < 0.05). For one-year actuarial patient and graft survival, incidence of delayed graft function (DGF), serum creatinine concentrations at 1, 3, 6 months post-transplantation, the incidence of cytomegalovirus (CMV) infection, post-transplantation anemia (PTA) and post-transplantation diabetes mellitus (PTDM) of both groups, there were no statistically significant differences.

CONCLUSIONPre-transplantation Hb concentration has significant effect on one-year creatinine concentration, but can not significantly affect acute rejection episodes, DGF, PTA, CMV infection and PTDM.

Adult ; Creatinine ; blood ; Female ; Graft Rejection ; blood ; Graft Survival ; physiology ; Hemoglobins ; metabolism ; Humans ; Immunosuppressive Agents ; therapeutic use ; Kidney Transplantation ; adverse effects ; Male ; Middle Aged ; Postoperative Period ; Retrospective Studies

OBJECTIVETo observe the effects of surgical delay procedure on the survival of perforator flap with three angiosomes in rat, and to explore its possible mechanism.

METHODSThe flap model was a perforator flap with three angiosomes which located on the right dorsal side of a rat based on the right deep circumflex iliac vessel. The two connection areas between the three angiosomes were successively named choke zone (CZ) 1 and CZ 2 beginning from the pedicle to the remote area. A total of 110 SD rats were divided into routine flap group (RF, n = 40), delay only group (DO, n = 30), and delay flap group (DF, n =40) according to the random number table. (1) In group RF, 30 rats were selected according to the random number table, and flap surgery was performed directly. Six rats were sacrificed on post operation day (POD) 0, 1, 2, 3, 7 respectively to collect the full-thickness skin samples at both CZs for HE staining to measure the vascular density and diameter. The rest 10 rats underwent flap surgery immediately after a catheter was successfully implanted into their external jugular vein. A volume of 1.5 mL sodium fluorescein solution (100 g/L) was injected to the 10 rats on POD 0 (5 rats) or POD 1 (5 rats) each time with a 2-day interval to learn the change in flap circulation. Each rat was injected for 4 times. The flap survival rate of the 10 rats was calculated on POD 7, and the configuration and distribution of the vessels in the flap were observed through angiography with the improved perfusion method of lead oxide-gelatin. (2) In group DO, the right thoracodorsal perforators of all the rats were surgically ligated through a small skin incision, and 6 rats were sacrificed on POD 0, 1, 2, 3, 7 respectively. The skin samples of each rat at the same area as in group RF were harvested to measure the vascular density and diameter. (3) In group DF, rats were treated with ligation surgery as in group DO, and then they were assigned and treated as in group RF on POD 7 with corresponding indexes detected later. Data were processed with group t test, analysis of variance with factorial design, and SNK test.

RESULTS(1) Significant differences of vascular density at both CZ 1 and CZ 2 were found on POD 7 among the three groups ( with F values respectively 2. 69 and 2. 76, P values below 0.05). The vascular density values of CZ 1 and CZ 2 of rats in group DF were (29 ± 7) and (31 ± 8) per mm on POD 7, which were significantly higher than those of group RF [(23 ± 5) and (23 ± 3) per mm2, with q values respectively 5.67 and 6.01, P values below 0.05] and those within group DF on POD 0 (with q values respectively 6.42 and 7. 14, P values below 0. 05). On POD 3 and 7, the vascular diameter values of CZ 1 of rats in groups RF and DF were significantly higher than those of group DO (with q values from 8. 15 to 11.13, P values below 0.05). The vascular diameter values of CZ 2 of rats in group DF onPOD 0, 1, 2, 3,7 [(65 ± 8), (63 ± 13), (69 ± 9), (67 ± 8), (64 ± 13) 230m] and in group DO on POD 3 and 7 were significantly higher than those in group RF [respectively (46 ± 10) , (40 ± 9), (43 ± 13), (46 ± 12), (47 ± 11) µm on POD 0, 1,2, 3, 7 ] at corresponding time point (withqval- ues from 7.29 to 10.79, P values below 0.05). The difference in vascular diameter between CZ 1 and CZ 2 was statistically significant in groups RF and DO on POD 3 and 7, and in group DF on POD 0, 1 , and 2 (with q values from 5.32 to 9.56, P values below 0.05). Compared with that on POD 0 within each group, the vascular diameter of CZ 1 in groups RF and DF and that of CZ 2 in group DO increased significantly on POD 3 or 7 (with q values from 6.12 to 8.13, P values below 0.05). (2) In groups DF and RF, blood from the pedicle ran through CZ 1 and covered the dynamic territory successfully within POD 7. On POD 0, the blood within all flaps was blocked for about 3 min after going through CZ 1 at 1 cm distal from CZ 2 in group DF and around CZ 2 in group RF. (3) Flap survival rate of rats in group DF was (95 ± 12) % , which was statistically higher than that of group RF [(80 241 9) % , t = 2.91, P <0.01]. All the partial flap necrosis occurred in potential territory. (4) Compared with the vessels in the left dorsal side without surgery, the vessels of CZ 1 in group RF were dilated obviously, and the boundary between vascular trees became indistinct, but the vessels in CZ 2 changed slightly; the vessels in both CZs in group DF were dilated dramatically.

CONCLUSIONSThe delay method could enhance the survival of potential territory in perforator flap with three angiosomes, and it acted mainly by dilating the choke vessels in CZ 2 before flap surgery.

Angiography ; Animals ; Graft Survival ; physiology ; Male ; Necrosis ; Perforator Flap ; blood supply ; physiology ; Rats ; Skin ; blood supply ; Surgical Flaps ; blood supply ; physiology ; Time Factors

OBJECTIVETo detect the stromal cell derived factor 1 (SDF-1) expression during the survival process of the narrow pedicle flap with hypoxia and ischemia and to investigate the role of SDF-1/ CXCR4 axis in flap neovascularization.

METHODSThe narrow pedicle flaps were formed on the bilateral back of 5 pigs. The pedicle ratio of length to width was 4:2. The flap size was 2 cm x 2 cm (group A), 3 cm x 3 cm (group B), 4 cm x 4 cm (group C), 5 cm x 5 cm(group D), 6 cm x6 cm (group E). The flaps survival rate was observed and HE staining was performed. The SDF-1 expression at the distal end of flaps was detected by ELISA during the operation and 3, 5, 7, 14 days after operation.

RESULTS(1) SDF-1 expression at the same group increased after operation until it reached the peak value at 5 days after operation; then it decreased to basic value. (2) SDF-1 expression in different groups was higher in bigger flaps until the flaps size reached 5 cm x 5 cm. Then partial necrosis happened at the distal end of flaps.

CONCLUSIONSThe SDF-1 expression may be related to the blood supply during the survival process of the narrow pedicle flap with hypoxia and ischemia.

Animals ; Cell Hypoxia ; physiology ; Chemokine CXCL12 ; metabolism ; Graft Survival ; physiology ; Ischemia ; physiopathology ; Male ; Signal Transduction ; Surgical Flaps ; blood supply ; physiology ; Sus scrofa ; Swine

Microencapsulation of cells or tissue fragments represents a potentially effective method to prevent graft rejection in allotransplantation and xenotransplantation without the need of immunosuppression, but the functional survival of all trial grafts is still limited. Usually, graft failure is mainly interpreted as the consequence of the progressive fibrotic overgrowth of capsules, the insufficient supply of oxygen and nutrition to the encapsulated graft, and the dysfunction of the encapsulated graft induced by small proinflammatory factors. These detrimental factors are interrelatd with the microcapsules, the implanted graft, and the transplantation site. This article reviews and summarizes the advance and the limitation of microencapsulated grafts transplantation in the above-mentioned aspects.
Alginates ; chemistry ; Animals ; Biocompatible Materials ; chemistry ; Capsules ; Graft Survival ; immunology ; Humans ; Islets of Langerhans Transplantation ; immunology ; methods ; physiology ; Transplantation, Heterologous ; immunology

BACKGROUNDHyperbaric oxygen preconditioning (HBO) is a new method of ischemia preconditioning. In this study, we examined its effects on skin flap survival and the mechanisms involved.

METHODSThirty-six rats were divided into three groups: HBO preconditioning, control, and sham groups. An extended epigastric adipocutaneous flap based on the right superficial epigastric artery and vein was raised. A 3-hour period of flap ischemia was induced by clamping the pedicle vessels with a microvascular clamp. At the end of ischemia induction, the clamp was removed and the flap was resutured. Rats in the HBO preconditioning group were treated with HBO four times before surgery. Microcirculation in the skin flap was measured on postoperative days 1, 3 and 5. The size of the flap was measured on postoperative day 5, before the animals were sacrificed. Samples of the skin flap were prepared and stained with hematoxylin and eosin. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the flap samples were measured.

RESULTSSurviving flap size was significantly higher in the HBO preconditioning group compared with controls, with a reduced inflammatory response and increased perfusion. IL-1, TNF-α, and IL-6 levels in the HBO preconditioning group were lower than in controls.

CONCLUSIONSHBO preconditioning improved flap survival in this ischemia-reperfusion rat model. The mechanisms responsible for this effect may relate to attenuation of the inflammatory response and increased flap perfusion following HBO preconditioning.

Animals ; Graft Survival ; Hyperbaric Oxygenation ; methods ; Ischemia ; surgery ; Male ; Microcirculation ; physiology ; Rats ; Rats, Sprague-Dawley ; Skin ; Surgical Flaps

The purpose of this study was to estimate the possibilities of an acellular matrix using a modified acellularization protocol, which circumvents immunological, microbiological, and physiological barriers. We treated porcine subclavian arteries with various reagents to construct acellular grafts. Afterwards, these grafts were interposed in a mongrel dogs' abdominal aorta. Six dogs underwent interposition with fresh porcine grafts (control group), and seven had interposed acellular grafts (acellular group). The control and acellular group dogs were sacrificed at 1, 3, 5 (n=2 in each group) and 12 months (n=1 in acellular group) after the operation. Histopathological examinations were then performed, to assess the degree to which re-endothelialization, inflammation, thrombus formation, and calcification occurred. The entire acellular group, but none of the control group, exhibited re-endothelialization. The degrees to which inflammation, thrombosis, and calcification occurred were found to be lower in the acellular group. We also discovered many smooth muscle cells in the medial layer of the xenograft that had been implanted in the dog sacrificed 12 months after the operation. These results suggest that the construction of xenografts using our modified acellularization protocol may offer acceptable outcomes as a vascular xenograft.
Transplantation, Heterologous/*methods ; Tissue Engineering/*methods ; Swine ; Subclavian Artery/*cytology/*transplantation ; Graft Survival/*physiology ; Dogs ; Cell-Free System/*transplantation ; Animals

OBJECTIVETo investigate whether electroacupuncture (EA) can promote cell survival and enhance heart function of mesenchymal stem cells (MSCs) therapy.

METHODSMSCs were isolated from bone marrow and expanded in Minimum Essential Medium Alpha (α-MEM). MI was induced in 72 Sprague-Dawley (S-D) rats by ligation of the left anterior descending coronary artery (LAD) for 30 min and reperfusion. MI rats randomly received injection of 1×10(6) DiI-labeled MSCs alone (n =24, MSC group), or plus electroacupuncture (EA) at Neiguan (PC6, n=24, EA+MSC group), or saline (n =24, saline group). EA treatment was performed for 4 days. Another 24 rats were subjected to chest-open surgery without LAD occlusion and treatment (sham group). Three time points, 4, 14 and 28 days (n =8 for each group) were included in this study. The survival of transplanted MSCs and the protective gene expression were analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot at day 4 and 14. Left ventricular remodeling, cardiac function, infarction area, fibrosis and capillary density were analyzed at day 28.

RESULTSEA can enhance MSC survival (2.6-fold up) at day 4. Big capillary density was 53% higher in EA+MSC treated group than MSC alone group. Furthermore, the rats treated by EA reduced the fibrosis and had 36% smaller infarct size comparing to MSC alone. EA also attenuated left ventricular remodeling and enhanced the functional recovery of infarcted hearts at week 4.

CONCLUSIONEA at Neiguan acupoint can promote the stem cell survival and improve ischemic heart function. EA could become a useful approach in stem cell therapy for ischemia heart diseases.

Animals ; Apoptosis ; physiology ; Cell Survival ; Cells, Cultured ; Combined Modality Therapy ; methods ; Electroacupuncture ; Female ; Graft Survival ; physiology ; Heart ; physiopathology ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; physiology ; Myocardial Ischemia ; physiopathology ; therapy ; Rats ; Rats, Sprague-Dawley ; Ventricular Remodeling ; physiology